Road, stream flooding likely in Somerset County late Wednesday

All that cold weather in the past week will mean an increased likelihood of flooding Wednesday afternoon after rain begins.

That’s because, even though it was warm Tuesday and will be even warmer Wednesday, the ground is frozen just below the surface, the National Weather Service explained.

It issued a Flash Flood Watch for a large region, including all or parts of Hunterdon, Warren, Sussex, Somerset, Morris, Union and Essex counties. The watch is in effect from Wednesday afternoon to Thursday morning.

“A slow-moving and potent cold front will tap the Gulf of Mexico, and it is forecast to generate rainfall amounts of between 1 and 2.5 inches,” NWS said, with locally higher amounts possible in prolonged and heavy downpours. Moreover, thunderstorms may develop.

According to the weather agency, prolonged and heavy downpours would cause flash flooding in some locations. Road flooding is likely. Since the ground is frozen just below the surface and plants are taking in very little water, heavy rainfall will not be absorbed.”

While flooding of smaller creeks and streams is possible, major river flooding is unlikely.